The development of topological quantum error correction (TQEC) codes such as the surface code has provided a scheme for error correction with a relatively high threshold that is commensurate with experiments [1]}, [2]}, [3]}, [4]}. While the physical requirements of the surface code are relatively straightforward to contemplate a two dimensional array of nearest-neighbour coupled qubits. However, for all physical qubit platforms, even with assumptions about quantum interconnects [5]}, the challenges inherent in the spatial arrangement of gates, and temporal characterisation and control complexity for large numbers of independent qubits to carry out TQEC are formidable. Since Kane's original concept for a 1D qubit array [6]}, a number of proposals have been presented addressing scalability issues, particularly with respect to the requirements of incorporating quantum error correction [7]}, [8]}, [9]}, [10]}, [11]}. In Ref. [7]}, a surface-code architecture was reported for impurity spins in silicon which was based on the dipole interactions between the P impurities. This work presented a detailed design introducing shared control, however it was limited to dipole couplings which are of the order of kHz. The difficulty of providing fast, available couplings in solid state architectures has led to several proposals. Pica et al. [8]} proposed a surface code architecture, in which electrons were shuttled between neighbouring qubits. Gorman et al addressed the problem of coupling by mechanically moving a set of probe qubits in order to establish the required couplings [9]}. Tosi et al [10]} proposed the use of long range couplings provided by a flip-flop qubit, a combination of electronic and nuclear spin states that can be controlled with a microwave electric fields. For donor spins in silicon, the incorporation of exchange interaction in surface-code based error correction schemes is still an open question.
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